Decoder and translator with readily changeable translations



F. K. LOW

July 15, 1952 DECODER AND TRANSLATOR WITH READILY CHANGEABLETRANSLATIONS 6 Sheets-Sheet 1 Filed Dec. 23, 1949 F. K. LOW

July 15, 1952 DECODER AND TRANSLATOR WITH READILY CHANGEABLETRANSLATIONS 6 Sheets-Sheet 2 Filed Dec. 23, 1949 nu UHU I P Y d.. 11.

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July 15, 1952 F. K. Low 2,603,716

DECODER AND TRANSLATOR WITH READILY CHANGEABLE TRANSLATIONS Filed Dec.23, 1949` 6 Sheets-Sheet 3 ,n Q 2v. SS E l b 8 c /Nl/EA/TOR "s By F l(LOW fwd ATTORNEY' July 15, 1952 F. K. Low 603316 DECODER AND TRANSLATORWITH READILY CHANGEABLE TRANSLATIoNs Filed Dec. 25, 1949 6 sheets-,sheet4 A TTO RNE Y July 15, 1952 F, K, Low 2,603,716

DECODER AND TRANSLATOR WITH READILY CHANGEABLE TRANsLATIoNs Filed Deo.23, 1949 6 Sheets-Sheet 5 /fvx/E/vron F K LOW 6 1.6 .7 .t e 0Umm NMS? Y2mm M se RW-H mw m0 m me NL1J../ m WFM@v E G. rw m B C wm Lm mb E KR HFH W R O T A L S N A Dn T m Awv 2n... 5w, 9mm@ 1D. 5 w 1 D y d dm J FPatented July 15, 1952 DECODER AND TRANSLTOR''WITHV READILYA CHANGEABLETRANSLY- TIONS Frank K. Low, Orange, N. J .,assigiior to Bell Tele-`phone Laboratories, Incorporated, New York, N. Y., a corporation of NewYork Y Application December 23, 1949, Serial No. 134,699

This Vinvention relates to automatic telephone systems of the commoncontrol type and more particularly to those types in which the physicalVlocation ofA a subscribers line ,on switches or switch frames does notcorrespond to its directory number. .l

, In such systems, as for example of the' crossvbar. type suchasdescribed in patent application s Claims. Cl. 179-18) of A. J. Busch,Seria1.No." 5 7,394,. led October 29,- 19458, which issued asrPatent2,585,904 on Feb- .ruaryI 1 9, 1952, the directory number is a ldecimalsystem number or a combination of letters and and decimal system numberin vwhich the letters alsoare represented by digits of the decimalsystem. The directory number yis the number dialed .fby the callingsubscriber byoperation of his dial or keys of the usual ytype .whichtransmits pulsesor other types of signals in the central .office toidentify the called subscribers station andline.v

. The ,physical or equipment location ,of ,the line towhich the incomingcall may be directed'must beidentiiied by a combinationof other symbolsfor. numbers specifying which frame,horizontal group, thev verticalgroup of lines and a` particu'- lar terminal withinsuc h. subgroup in,order5 for the equipment to establish a connectiontosaid linel lInaddition, the typeV of ringing'cu'rrent Ior signal required for' thelinel and otherfspecialinformation-about. its type andtype of service towhichit is entitled must also be .designated by various'ptherrepresentations' or numbers. In lorde'rto provide the necessary amountof nexibility to properly distribute 'thetraic throughout switches in.the office, theline locationV information aswell asf the ringing andother information can not .be identical with the .directory number yetmust be. derived from it..

Itisfurther required that the relationship between. the directorynumbers. and the equipment location ,and additional .infomation relativeto the various lines will be readilychangeable becausetraflic loads onthe switch framesyarybecause directory numbers and other changesV aremade, and .because itis undesirable to continually change directory'numbers at short intervals to compensateI for these various changes.

It iscominon practice in systemsof the type described in theabove-identified patent applicationl of Busch to decode or translateadirectory number dialed by a calling subscriberinto anew series vofnumbers Vor designations corresponding to theequipment location'of theline, the type of ringingsignal and suchj'other infomation as may be'desired or required by'thefswitching ap- 2 paratus. With the aid ofsuch decoder or translator; avmark'er, or other comparable common4control circuit or circuits, is enabledto establish the desiredconnection vthrough the switching equipment to the called line inresponse to the dialed directorynumber.

It is an object of thepresentinventionto per- :for'm the decodingandtranslating functions in common 'control telephone switching` systemsby vmeansof'electron tubes so as to reduce the time required for theestablishment of conversations and thus increase the call carryingcapacity of a telephone,switchingofca Y v t,

It is afurther object of the invention to provide a crossconnectingfield lby means of which changes in the relationship between thedirectory number and location of the line on the frames and equipmentcan be quickly and expeditiously made. l

A feature of the invention relates to a coordinate array ofcross-connecting points, each point 'comprising a jack or socket intowhich a low pressure gas conduction tube may be inserted forestablishing the desired cross-connections.

The foregoing and other features of this invention may bemore readilyunderstood from the following description when read with reference Y tothe attached drawing in which:

Fig. 1 shows in outline form various switches and control circuitsemployed in establishing the connection from an incoming line or trunkto a called subscribers station under contro-lk of a directory number; Y

Figs. 2, 3, 4 and 5 show in greater detail an exemplary arrangement ofcertain elements of `a marker circuit which cooperate with the decodingand translating equipment as well as details of the decoding andtranslating equipment employed as the so-called number group circuit inaccordance with this invention for translating the directory num-ber ofthe called subscribers line into numbers or other indicia indicating thelocation of the line in the switching system and the type oi ringingcurrent required, and any other additional information which may bedesired or required. This additional information may assume manydifferent forms including types of terminations o f the line, types ofsupervision, type of party line subscribers station, type of service towhich the line is entitled, transmission requirements, etc;

Fig. 6 shows a perspective view of the' cross.-

connecting array of thev tube sockets with tubes Y inserted incertainofgthem to form across-conf readily changed by merely changingthe location l kof the tubes in the various tube sockets; and

Fig. 7 shows the Vmanner in which Figs. 2, 3, e

and are positioned adjacent to one another.

Fig. 1 shows in outline form various component rwibsgedSwitchingapparetus fer establishing a typicalgcall through a cross-bar`svvitching system Vof 'th'e'type described in the above identifiedBusch'application. Line 9 represents an incoming. .4

trunk from a distant switching cen-ter and is ter'- mina-ted in anincoming trunkfcircuitgjl(1.;I `When the trunk circuit is seized at thedistant oice', a'

, fromanyother office.V These incoming trunk circuitsV may employ thesame or .diierent'incoming register links to establish `connections fromthe incoming trunk circuits to idle register Vcircuits. Y- jUpon thevestablishmentof a connection to an'idleincoming register circuit, asupervisory signal is transmitted through the incoming regis- YterY linkH and the trunkY circuit termination l0 and over trunk 9 to the distantcentral oice.

Upon reception of this signalthis central ofce willtransmit thecalledsubscribers directory number by .means of suita-ble pulses orothertypesofrsign'aling current or currents. "These pulses aretransmitted from the distant oiice over trunk 9 to -the incomingregister circuit I2 where they are recorded or stored by the registercircuit and itsassociated equipment.

yWhen Vthe number has been substantially completely received andadditional informationrelative..to lthe particular incoming trunkcircuit and its location on the's'witching frame has also been,recordedin the register circuit, the registercircuit will advance andactuate an incoming register-marker yconnector i3' to establish aconnection between the register and an idle marker` circuit. l L f llWhen this connection is established the directory number of the calledsubscriber is transmitted .to the marker circuit which'marker circuituses the thousands designation to .sel-ect one of the various numbergroup circuits20, ZI and 22. Upon the selection of such a vcircuit whenthe V4- the marker circuit. The marker then tests the possible pathsthrough these frames from the incoming trunk circuit 9 to the calledsubscriber I 9 and upon finding an idle path establishes connectionbetween these lines. The marker will then ,cause the proper ringingcircuitstosfunction to "apply the proper ringing?V potentials to thesubscribers line' after which the marker circuits and related controlcircuits are free to aid in Jthe establishment of another call.

"When thecall'ed party answers, the talking battery supply andsupervisory circuit is established and nat the termination of the call,the switches are restored to their normal or idle positions,thusinterrupting the connection between the incoming trunk 9 and thecalled subscribers line I9.

The present invention relates tol electronic means and methods forreceiving, decoding and translating the called subscribers number intoproper indicia for designating the locationv of the called line upon theswitch frames or switches. v i l v The number group circuits areillustratedY in Fig. l by rectangles V20, 2| and 22. Only three vof thenumber group circuits are representedhin Fig. 1. It willbe understood,however, that any suitable number of such circuits may beprovided asmaybe required `be the number oflines terminating in the central olice. Y fl Likewise, only one vmarker circuitand'fone line link frame .and onetrunk link frame and 'one representation of other control circuits areshown in Fig.f1.l It is to be understoodvofcourse, that the variouscircuits, ramesand other telephone equipment will be duplicated as oftenas necessary to handle the desired or necessary volumeo'f tracv anddesired number oi subscribers stations. Y

In other words, the number of number group circuits in an oice dependsupon the number of subscribers, there being one number group circuitfori each Vthousand subscribers. In, addition, usually more' than one.marker circuit is provided, but the circuits are so arranged'that Yonlyone marker may be connected to a particular number group circuit at anyonetime. Y i

In Figs. 2, 3,` 4 and- 5', when Fig. .3 is arranged to the right of Fig.2 and Fig. 4below Fig. 2" and Fig. 5 below Fig. 3, the circuit detailsof the? number group circuit together withA certain vportions circuitbecomes idle, the marker I4 transmitsvv the directory Ynumberzof thecalledsubscri'berto the number group circuit. The number groupcircuitthen .translates thisnumber into other numbers orindiciaindicating the location of the called .line as well as the classof service and ringing current required and trans-mits suchindic-ationsto themarker circuit. Thereafter the marker `may disconnectthe number group circuit so this circuit Ywill be available for use inestablishing other connections.

The marker then employs this information together with the informationrelating to the lo.- cation of the incoming trunk circuit to establish apath from the incoming trunk to the called` subscribers line such assubscriber i9. In establishing `this pathy the marker rst vactuates thetrunk v line .connector l5 and Ythe linevlinkconnecto'rs l1;

which. connectors establishr connections between of the marker circuitVwhich cooperate therewith are shown in detail. Fig. 2 shows the portionof the markercircuit in'which the directorynumbper is recorded orstored. A

"Fig.3 shows the .decoding arrangement Vem.- ploying a plurality ofvthree-element gas tubes. Fig. 5 shows the cross-connecting fieldwherein cross-connections may be made from the decoded directory numbersof called stations to a plurality of leads representing items ofinformation s ubsequently used by the marker in extending the connectionfrom the incoming trunk to the line link frame. Fig. 4 shows a manner inwhichthe information from the numbergroup circuit is recorded in themarker circuit.

In the upper part of Fig. 2 are partly shown andv partly indicated foursets of relays 201, 202, 203 and 204 used by the marker for registeringthe four-digit directory number of the called party after these digitshave been transmitted to the marker from the incomingregister.v circuit.There are five relays in each of the four sets. The numerical vvalue ofVeach digit is indicated by the operationof aparticular two of thefverelays in; the 1setftheother three relays remaining unoperated'.` VForiexample,; inthe thousands digit registerthe digit; "1 is registered bythe opera- .tionof relays (THD) and ('IHI), the digit .2 by they'operation'of (THU) and (TI-I2), etcg, The .digit.f0 is registered bytheoperation of (TI-Il) and-,GTH'D .1, Five relays -used in `a similar`mannerare provided for; registering each of the other three digits,namely, hundreds, tens and units.

.-When the marker receives a four-digit number corresponding to theterminal ofthe called party, it -usesthe thousands digit `te determineto'which number group it will connect. The setting of the relaysTHll-)p(THVI), (TI-I2), (THD and (THT) inthe thousands digit register preparesa'. path 4forgseizing the particular numberl group circuit provided fordecoding thek one-thousand-threedigit-numbers identiiied by thethousands digit register. Forexample, if the thousands digitis 5,1 thenumber group chosen will be that one provided vior decoding numbersbetween 5,000 and 5,999. The .three-digit number registered on thehundreds,- tens and units registerrelays'constitutesthe-inputinformation sent into the number group-circuit. y Eig.. i showsor indicates six sets `Aof Yrelays 4N, All 1,1112, :413, `4,415usediorreceiving and registeringf, outputv iniormationlirom. the .numbergf urrcircuitjfone receiving relay of each ofthe .setsnsuch asthe(F'I'Nyrelay, for example, is'operat'ed by the number-group circuitfollowing th'l'atters decodingand translating function. The lrecei'vi'ng'relayl in Y turn operates andgloclrs an rb .uxiliarytest relaysuchas(FT-T3), for. examplawhichcontinues to store theitem. of inirraton itr`represent's after thevnumber group hasbeen discharged. NThe -tensdigitof the frame number. on whichthei calledlineterminal is lo' cated ,isindicated bythe operation` of one of the f ourrelay's designated(FT'I'U) to (FITS) in the upp'jerfj, group, designated.. 410, of the six4group' series. The unitsdigit of the frame number is indicated bytheoperationof one of ten similar relaysin the group designated frameunits numberffy Similarly, the number or the 1 vertical group, that. ofthe horizontalV group, and that of the vertical iile (the iinalsubdivision oi a vertical group) vare all indicated bythe operation loi!one relay in each of the sets designated vertical group, number,horizontal group number" and vertical iilenumber, respectively. The typeof ringing signal required for signaling thelsubscribers station isindicated by the operation of one of the fifteen relays designatedRC'IIU'I) to (RCTIS) in the group designated ringing Ycornbinationnumber. QI, addition to the digit register'V and Youtput information*,relays, the controlrelays of; the irarkerV directly concerned; withthe seizureand 'opera'.'tion of the associated number group'circuit areshown'. y lWhen the marker reachesfthat point'in its operating cycle atAwhich it is necessary to call for thejservices "of a Inumber.groupcircuit, vcertain preparatory steps are" taken among which are theapplication' .ofy oi-normalig'rounds to several oi the relaysshown inFigs. 2` and 4. y'lihese Aoil"- n'orm'al ground supplies are,establishedv by fthe (,:blperation oi relays (FLG) (FLGD-and (NGC)whose contacts areindicated by dotted lines but which `are Anot fullyshown.. Thef'oifnormal groundisupplied by the (FLG) relay by way of abrealccontact on CKO- operates .(SNGZ) relay.' (SNGZ) in turn operates(UC) relay and `supplies battery potential to several leads andpartially nector vrelay (MCA-B) lishes connections between the hundredsand tens acuario closes a path over which seizure of the number groupcircuit is effected. r x The actual seizure of the number group startsrshortly after the operation 'of (SNGZ), when the y(TKF3) relay of themarker operates. The operation of Athis relay completes a circuit frombattery through the NGS lamp, through (SNG2) and through two previouslyoperated (TH-) relays in the thousands' digit register over the ST 'leadto thev (MP) relay in the number group :cirv"cuit whose block of onethousand Lnumbers corresponds to the thousands digit and' to thev num-*ber of the energized ST lead. By way `of example, it is shown that leadST5 in Fig. 2 is connected to the (MP) relay in Fig. 3. r'I'his is``based on the assumption that the thousands digit registered was thedigit "5 and that the (THI) and (THD relays had been operated.

The (MP) relay is one of a chain of marker preference relays within thenumber group cirother marker circuit operate the same-thousands digitregister relays in its own circuit,'it `would make a connection toanother marker preference relay in the chain. The purpose ofthe v chainof marker preference relays is to establish ra connection from the rstmarker circuit which `operated one of these relays to the connectorrrelays in the number group circuit, and to lock out `other (MP) relaysand connections fromother ymarker circuits seeking the same number groupiframe.

When an (MP) relay operates, it operates con- The (MCA-B) estab- `digitregisters over leadsV HBU-S and TEU-9,

,respectively, to electronic decoding circuit of the vnumber group frameshown in Fig. 3.

The (MCA-B) relay also completes connections from battery potentials vialamps BSI, 2, 3 and 4, the

contacts of previously operated -relay (SNGZ), ,over leads BSL 2,`3 and4to the windings of additional connector relays designated (MCA-VT),(MCB) (a two-section, two-coil relay) and (MCC). The (MCA- T)connectorre'#r lay, in operating, establishes connections between theunits digit register via the previouslyv 'operated (UC) relay and leadsUU-9i to the decoding" circuit. of the number group. It also establishesconnections between the frame tens number` and `fratrie units numberinformation receiving relays y*over leads vvFT-S vand, FUD-v9 to theoutput vof the translating circuit of the number group shown in Figui.Connector relay (MCB) estabflishes connections between the verticalVgroi'ipl number, horizontal group number and Vertical iile number Yand' ringing combination number in# formation receiving relays to theoutput of the translating circuit. (MCB) also closes the UK 'leadwhosefunction is described later and leads WL," WF and WGJ These latterleads per-v form essential functions in the joint operation of thenumber group and marker circuits of the type disclosedinthe copendingBusch application.v

They are notrequired, however, for the num#Y b ergroup circuit describedherein. Connector 'relay (MCC) closes leads S0-9," SCK andv TNK whosepurpose is .described later.

All leads shoyvn'c'onnected to the ma'rlnerr side of connector relays(MCAB), (MCA- T), Y(ii/ICEX v`and (MCC) arelmultipled to correspondingcon# tactsfonfsimilarf:connector .ffrelays :in Yall fothr number groupcircuits thereby.l permitting'fthe' marken under consideration* toffbeconnected to any numberv .group "circuit, depending, of course,

' enm/hich combinationr ofthousandsdigit register relays fareioperated.All leads- 'shown Lf'eonnected to" Ftliellnumber group side of' thecoimectorsrelays are multipld tol corresponding contacts' onothersiin'i'lar'connector relays Within theinumbeng'roupcircuitfiunderf'consideration 'but '-'associa'ted with other: markercircuits, therebypermitting the.

number group circuit underrconsideration to Abe connected-to 'anymarkervdepending von which -re'- i layinthe. chain of marker preferencerelays-is operated.. The decoding Vcircuit'fshowrrrin Fig; '3 employslllithreeeelement gastub'es for-reducing; a threedigit number -to abasis ofone marked lead out of, a

thousand.' In'ordertomake tlie'd'escription of opration `of this circuitmore clear, suitablezworke ingrvoltages will 'be assturied'.` z Withvthenumber group fco'nnector :relaysf i-havin'g #been l' operated,e50evoits2is applied through relay Wndingsland designated- DE@ .to 99vare connected ,through resistorsttc'rcross-connectingv punch-ingsP'Itlito P5119.y The` one hundred resistors 'involved comprise; tengroups of vten resistors each'. Thef ten resistors associated Withthecathodes of ltubes .lto- BSD-all o'f. Whosezanodes are connectedtoxtliefffHB? lead; are connected. togetherV ats tloeflfll-punching.lSimilarly; each other-group: of' tenresistors is consociated with thesame group of ten tubes. It is requiredthat each PT- punchingbei-cross-c'onnected to onebut only one of the'threemearby punchingsdesignated PN; TN and 'PTNagf These punchings" through contacts of-tlieapreviously operated:v (MCA-+B)- relay are eonneoted'through the'low resistance windings of relays (PN),('TN): and` ('PTNlitoVA -50Yvolts; The purpose otjhe PN, AI'Nf and 'PTN punchingsf'a-nd :associatedmarker relays is given later.: .The-cathodes of the. one thousandtubesdesignated to 999 are con.

Y Vnected through an individual resistor to acomf mon;lead designated"UKJ This lead passes through the (MCB), jconnector relay Vand throughthe.-1 0w;resistanceVwindingfoffthe (gUK.) relay-in r Y reason' of theprior operation of- VSNQZ-l, MCA-1B) r andf (MCA-f -Tl relays. thehundreds,gtensvandfuntsdigits ere-now presti-'1t-4ed=tothe-nurnber-groupinltheformpf +130, volts 4 on oneead out :of eachor the tenleads in the. HEI-T331 and U- groups,--:Since.-g-5 0voltsfap-- parson all decodertube cathodes the applica-j tion.Vofy-i-lBO voltsto one of. thel TB' leads fr-estrie control 4gapsoffallten tubes in the. corresponding horizontal row.; Positive 1?*0 .voltsonone of the HB- leadsvputs potential lontlieh anodes 4of all.ten tubesin the y.correspending verticalrovv.vr A main gap dischargetakesfplae,only. vinfthe tube located at the intersection-of the tens VandVhundreds leads because-only this one tube Willhave` both its controlgap-redand anodepotential present. The lforegoing,action constitutes atens selection. and5 causes the p074 tential. of .one vof thehundredtens-busbars tor Volts. When the main gap dischargeftakes plage;

the` potential betweenA thel Yanode-and cathode Y drops to a value1intheneighborhoodof 80- volts.

benapplied-by :Wayff one 'of'fthe Uiwlads to thej-'anodesfofthfoneehundred tubes inthe-corresponding' horizontal row o'f 'units'tubes; lthe "tube attnefinterseetionf will ffre across its.' main gapandfthvusjcausejtnerpotntialoaone o tu 'thousand units-'I verticalVlbust-bars to 'fciiage `vfrom #LjQ "fvolt's'tofapproxirhately-i150volts.l vThis' latter sation 1j;i;tmstintjujtts the ftun'tsA selectionand fcomprete t A j mee each one/fof' the units busi-bars' correspondsto one of the' -onefthousandffdirectory .puin-ters" served by rertysl in1111s. cathode; mirent .ptsises-thtougjhlth *winding 'Q'fthe 'jay inthemarker 'Whichbprates nga cneekof'thenumber giroupcrcuitop erationupidthspoint 'The'eumfthese three checks results Vin: theope'ration Q'f'tliefhundreds,' .tens and units fcheckz relay, (HTU.K)."v`If a cir. cuit Eiult shouldr'esult in the: operation lo mce tlf1 'a11.jfone`@the".(PNQLTNY :0r PTN), ref layfs, ffthe terconnection'glof thevconta-'cts of these-"relays isf such las td prevent the op- In auditibnto the checking'func the; (EN.) TN and tern) relay wde'sbrfitel lsoidentify the' numberjtcalledasvto its-physical:ortheoreticalclassification. i In A-.some .oices the Itdirectory nurnbersare.tjlivideo'lt into groups lso thatserviee to these numbers may berestricted in accordance with theforignin ofgjthecall-. Thesegroups-.arelof one hundred lines each and are. divided betweenthreenclas lines representingfphysealltheof 'a1-,zing i'u'unbersg`A Insome to twt 'otite ,efodesffor bei'rs. previously*idicatedach-Mdck dronetenermi-numbers- 'as represented by neloftth PTlpunchingsaconnected-itoi'one v of the? tlii'ee punehingsPN, TNabr' RTN-"represe'ntingia 'physii eration et fthe relay. Any ,faultwlilich nts;thetperationlof., the' 'rrrUK jre1a;y

a. trouble@,irulicatioriv .on"equpment associated calnumber, atheoretical number or a. nonedis'- crirninating number, respectively. Bythis means the lgroup designation of theI called line is given to themarker in the form of an energized (PN), (TN) or (PTN) relay. Thisinformation is utilized by the marker through the medium of contacts,not shown. Y

Figs. 4 and 5 show the translating and crossconnecting grid employingone miniature gas diode per item of translator output information foreach directory number. The horizontal bus-bar to vwhich one terminal ofeach diode is connected is supplied through a resistor with a voltage ofapproximately -90 volts which, together with the -50 volts normallyappearing on the vertical bus-bar, results in a voltage across eachdiode of about 40 volts, a value below the breakdown limit l O f thediodes. vPositive 50 volts on one of the units bus-bars, however, firesall the gas diodes on this Vparticular bar installed as cross-connectorsin the translator grid. The firing of each diode will cause thepotential on the correspondinghorizontalbus-bar to change from -90 voltstoV approximately-30 volts on the basis of aV diode drop of 80 volts.Each horizontal bus-bar is. capacitively coupled to a gas triode whichacts as a Work tube. These tubes aredesignated FTD-3, FUD-9, etc. .Therise of. 60 Volts ona horizontal bus-bar triggers the corresponding gastriode which in turn causes operation of the corresponding receiving-relay in the marker circuit. With -30 volts on a horizontal bus-bar,backups into other, diodes on the same bus-barwill..

not occur since such diodes Will have approximately -50 volts on theirother electrodes with' a resulting non-operate voltage of about volts ascompared to a noneoperatecapability of 60 .tov

6 5 volts minimum.

There are sixgroups of output information from the translator grid. Thefirst and second groups together tell the line link frame location ofthe called number. In one ofiice there may be as many as forty line linkframes. translator group has four horizontal bars which tell the tensvdigit of the number corresponding to the location Vof the line linkyframe. These bars are designated FTD-ETS. The second group tells theunits digit ofthe number corresponding t'o.

the linelink frame. This group has ten bars designated FUU-FUS. Eachline link frame may haveas many as fourteen vertical groups of lines ofiive lines each. The third translator group has, fourteen horizontalbarsdesignate'd TVG!)- VGI 3V and they tell the vertical group. locationof the line'.` Each line link frame also'has ften'hori'- zontal groupsand the fourth translator group has tenj horizontal bars designatedHGU-HGS to determinethe horizontal group location vof .the line.

The fifth translator` group has Vfive horizontal:y bars designatedVFU-VF4 anddenotes thevertical iile number or the location of the'individual calledline within lthe ve line vertical subgroup The lasttranslator group determines'the ringing y combination required to signal.the particular l calledline `and station. This group'has fifteen-135horizontal bars designated RCD-RCM to' deter'- mine the side of the linetozwhich ringingvol'tage should be applied, the polarity of the voltage.

and whether or not ringing signals shouldbe ap-vl plied in codecombinations. One of these fifteenl Y'horizontal'. bars, the RCIU, isused for the special purposev of. signifying that theA called number isthe first number of a P. B. X group of lines over which hunting isrequired. When one diode 'in each of these six translator groups hasbeen fired,

The fllSt L 10 the physical location and required ringing signal of thecalled'line-are made knownto the marker. When one of-'th'e fourtranslator output work tubes FTB-3 fires, the associated (FINO-3) relayoperates. The (FTN) relay in turn operates the corresponding (FTT-)relay known as a test relay Whichextends its operating ground to the(FPL) relay which also operates and locks.- The locking of the (FTL)also locks operated the (FTT) relay and holds the latter beyond thepointv at which the number group circuit isrreleased and at 'which the(FTN-) relay is also released. The (FTL) is common to the frame tensgroup and serves to hold ani7 one of the previously operated v(I""'IT)relays. Through the medium of contacts not shown the (FTT) relayprovides the. registration of the information item it repre# sents andWhich is used later by the marker in obtaining access to the calledline. '.One'relay: out of each set corresponding to the (FTT) isoperated in each of the other ve sets for record'- ing identificationinformation as to frame units number, vertical group number, horizontalgroupv number, yvertical file number and 'ringing combination number.Also, the loc relays in eachl of the other iivesets is' operated andlocked.` These .are designated (FUL), (VGL), (HGL), (VFL) and (RCL). Thelocking circuit forall six lock relays is underl control ofthepreviously: operated LLI. Oncalls other thanfthoserequirr ing a lineAhunting operation, suchV asthe case of.. a P. B. X trunk group,'thepoint at which all sixlock relays operate marks the end of the numbergroup decoding and translating operation Tand the point at which thiskcircuit may be released and made free .to serve other calls. Therelease' of the number group circuit Vis initiatedby the completion of achain circuit Knot shown) through thesix operated lock relays whichcause theoperation of Ithe release number group" relay (RNG) (notshown). The operation of (RNG) releases :(SNGZ). and the off-normalground 'spply .relay (NGC). The release of (SNGZ) re.- leases the'marker preference relay (MP) and all of the 'number group connectorrelays.

extinguished and the circuitrestored to normal. The release of the (MP)relay recloses the marker preferenceV chain circuit which makes itpossible for another marker to seize the number group by operating itsassociated (MP) relay.

.In-the;V event' the called number corresponds to 'a P. -B. X(privatebranch exchange) group of" lines, it is necessaryy for the markerY toknow which lines of the group areidle, to select one of thegroup, and tolearn from the number group circuit thev equipment location of theparticular lineselected. P. B. X lineAgr-oups ordinarily containtenrorffevver'lines and the group can-be identified by the thousands,hundreds and tens digit'of the directory number. When such groupsare,.present an (SC`) relay is Across-connected tothe appropriatepunching in Ythe seriesV designatedTBU to TB99. -When one of the tenstubes -(l00lto 99) in Fig-.13 is fired, the resulting cross-connected tothe series'of NSU-9l punch# ings, to leads"S to'"S9 leadingto themarker.` Thesenpathsprovide a means for testing the busy With i theserelays Areleased the number group tubes are or idle condition of theline sleeves by means of the (SLG) toA (SLS) vrelays inthe marker.v Y

When theA directory number received signifies that a P. B. X is beingcalled, inaddition to pro.- Viding for the operation ofthe appropriate(SC) relay as described, 'it is also necessary to advise the marker thatthe latter shouldltalre steps .t0 test the P. B. X group 'of lines. Themarker vis given a signal to this effect by thev placementof the ringingcombination diode in the translator grid at the intersection of theunits bus-bar corresponding to the directory number` and the ringingcombination number l0 horizontal busbar. )This diode cross-connectionAresults in the firingof the RCI!) tube, the operation of the (.RCNIU)receiving relay and the (RCTID) -test relay.. IIfhis particular testrelay, howevenis un,-l ablerto 'operate and lock the (RCL) at this timebecause the path to the latter is open at the contacts of, theunoperated (CICR.) relay. Instead, the (RCLS) operates(PBXl). and'(PBX2) relays which set up circuit conditions that will result incanceling the units digit initially. given to the decoder, thecancellation of the received;infor mation; fromv the' translator,` thetesting andi-selectiiongofgan idle line within the P B. X group,A

the; transmission to the decoder of anew units digit (in accordance withthe above selection), a; second decoding fandV translating operationandthefregistration of .av new.r set of Asignalsonthe in:

formation receiving relays identifying 'thel equipe ment locationof theparticular P. .B..,X line .selected.

with the (PBXI) vand (PBXz' relays operated,V relay operates over thelSCKf the (SLCK) lead.v from battery on thecontact of the (SC'-) relayin .the number group. (SLCK)` in turn opcrates relay (CKO) through apreviouslyY closed chain circuit through all lock relays excepting (CKO)locksto (NGC) ground and` the (RCL). releases (SNGZ), (UC) and (LLI)relays.- (SNGZ) :releases connector relays (MCAf-T) and (MCB). (MCC) areheld .operated by. virtue of contacts kon (PBXIXmaintaining *50.voltsfonleads.ST-- and BS4. The vrelease-ofrelay (UC) together with thefprioroperation of (PBXI.) operatesrelay(SLC) 'which Vva'inally closes theconnections between' sleeve test relays SLI] to SL9 and theA ten orfewerline sleeves via (SC)V relay operated and punchings NSO-9. r(LLI) relayin re.-'

leasing releases all lock relays and associated information relays, thuscanceling the previously received information. The release of relay (UC)withdraws +130. voltsfrom the anodesl of the units tube thus restoringthe latter. The release of connector. relays (MCA- T) and (MCB) releasesthe information number relays and restores to normal the tubes in thetranslator` circuit.

Connector relays (MCA-B) `and leases, (SLC) ,'Ihe; (-RCTIB), relay:havinglbeen. previously released fiOllowingrelease of (MCB) andjl(RCNHDj, and the lockrelays having been; releaseza chain oruit isclosed ,for operating (CKR). (CKR) causes the'reoperationfiof (SNGZ),and(l .Ll ',Ihe-recperationLofySNGZl causes the reoperation of'connector A relays (MCA-Jr) and (MCB) Vwhichfcomplete theVreestablisments -of alll connections between-the markerandthenumbergroup. f1. Y

,A new units lead now being energized by, the application of +130,volts, a new unitstube will reand energize a new vertical'bus-bar in thetranslator grid. The particular pattern of dif. odesA installedwill nreand .cause the transmis-f sion to.VV the marker informationmelays f anew setof information delining the .locationlofv the P. vB. X linefinally selected'and also .identifying the type of ringing signalrequired. Since on this nal phase of the call someV (l5'.(3T -)Y relayother thanv (RC'Il)v will operate, *theA (RCL). will operate withtheresult that a chain circuit (notshown) through all lock relaysVWill-becompleted and will operateA the (BNG) relay, (not shown) forreleasing the number group circuit as previously mentioned in describing.a Vcall not lrequiring P, B. X hunting. if

,Incase the switching system under-considera# tion is used as atandem-switching point, tandem. trunksappear on the line linkiramesandfincome ing calls destined 'for these trunks require/the` useof the number group circuit just as if 'these' calls were Vdestined forsubscribers`V lines. In such va case thenumber of the .tandemtrunk isifurnishedv to the number group circuitintheV usual way Vbut becauseofits. special meaning a ,(TN-) relay shown inthe upper partfofv Fig.'3- is cross-connected to one of the TBUD-toTBSS punchings. TheoperationV of this relay'furn-ishes azspecial ground signal overther-(TNK) leadI tothe' marker with the result that'the marker isadvised that the. number in .question pertains to a tandem trunk sothat-it can take appropriate' action in completing the connection.` f

InEig. part'of a model translator cross-con-Y necting grid yis shown.Mounted above an insulatingpanel 69 are a series of vertical barsr 60,-6l, 62, 63, 64, etc., 'each barf being punchedwith as many. -holes asrequired for all-possibleitemsv oftranslator output information;indicated in previous paragraphs the total wouldbe fifty-- eight for theNo.l 5 cross-bar-otlice'number group; Y' These holes are suitableforre'ceiv-ing` the miniafV ture'bayonet; base type tube-sucha's u50.Under# neathv the'bank ofvertical bars and'V at right angles to them/area series of multiple contact strips 10, 7l, 12,;13,`etc., mounted oninsulating panelv "T9-,-l and-arranged so that -an individual springcon- Y tact finger is under each hole 'of the verticalbars.y

Those sleevetest relays Vin the (SLUTQ) grouplJ whosewindings-findfvolts (idle condition) onl :corresponding line sleeves, rather than lground,v (busy condition), willoperate andY in turn i operate andflockauxiliary-relays (SAUfS). VA

chain .circuit through contacts of thelatterrelays causes` the +130vo1tApotential supplied through ther .units digit register (previously setrin accordance with the units digit of the P. B. X.

directorynum'ber) to be applied tothe U-I lead corresponding tothe'iirst line sleeve, in ascending numerical order, found idle asVindicated bythe lowest numbered (SA) relay operate.

Following the operation of one or more (SA)V relays thef(SAE)operatesand this in turn re- Thetube isfully inserted .and then givena-tur'n'f so thatits' two radial pins will 'findV correspondingxdepressions in the underside of the vertical bar 'and;thus.lock.This multiple-socket mount-VL ing cgi-'the basic cross-connectinglelements fai .cilitates quick; .changes indtranslat'or output in-Wformation whenline J changes'lv are reduiredl "duel to:tralicqandadministration conditions.

A vvariation to the above-'described .system .'of'. decoding a,three-digit numberl may beprovided' by the use'of one thousandfourelement gas tubes4v instead of" the eleven hundred .threeelementf'tubes.V The tube required]` is one in-which the.: control gap' isseparate from-the 'main gap. In

orderto bring about ionization within'the ,tuber l.

and have the discharge transfer-to the main gap, l

accenna,

itgis necessaryl tohave va particularpattern of threepotentials presentvin addition to -50 volts on the cathode. The control anode, controlcathode and main anode potentials are applied on a decimal system basissimilar to that previously described. Only one tube will re because onlyone will have all three potentials present.

In addition to the above, minor'changes in potential conditions willpermit theuse of dry rectiers or other unilateral or non-linear cells aslcross-connecting elements diodes, sinceA these elements meet the basicvre,- qui-rements of the translator grid, namely,t`o 'extend a voltageof a given polarity signal from a given vertical bus-bar to itscross-connected horizontal bus-bars but not to allow the reverse orderof transmission.

What is claimed is:

1. In a translating device, a plurality of code points, a plurality ofoutput circuits, means for interconnecting any of a plurality of saidcode points to any of a plurality of said output circuits withoutinterference one with another which comprises a code point conductorinterconnected with each of said code points and arranged in accordancewith one coordinate, an output conductor insulated from said code pointconductors interconnected with each of said output circuits and arrangedin accordance with another coordinate, a non-linear circuit element,means for detachably supporting said non-linear circuit element incontact with one of said code point conductors and one of said outputconductors adjacent the interconnection of said conductors, and -meansinterconnected with each of said output circuits responsive to anapplication of a predetermined potential condition to any one of saidcode points interconnected therewith through one of said non-linearcircuit elements.

2. In a telephone switching system of a common control type, translatingapparatus for translating dialed signals representing a directory numbercomprising a plurality of code points, a plurality of gaseous conductiontubes, means operative under control of dial signals representing twodigits of a directory number for selectively initiating a dischargethrough one of of said tubes, a second plurality of gaseous conductiontubes, means operative under control of other dial signals representinganother digit of a directory number and said discharge through saidselected tube of said first plurality of tubes for selectivelyinitiating a discharge through a tube of said second plurality of tubes,apparatus responsive to said discharge through said second selected tubefor applying a predetermined electrical condition to one of said codepoints.

3. In a telephone switching system of a common control type, a pluralityof lines, a plurality of code points, translating apparatus fortranslating a plurality of series of dial signals comprising a pluralityof gaseous conduction tubes, means interconnected with said tubesresponsive to two series of said dial signals for selectively initiatinga current discharge through one of said tubes, a second plurality ofgaseous conduction tubes, means interconnected with both of saidpluralities of tubes responsive to another series of dial signals andsaid discharge through said selected tube of said first plurality oftubes for selectively initiating a discharge through a selected tube ofsaid second plurality of tubes, apparatus connected to said tubes and tosaid code points responsive to said discharge through said secondselected tube for lapplying a predeterinstead of Agas mined L electricalcondition to, one of. said co'de.

points, la pluralityl of.; outputcircuits designating.

theV location of said lines an'ddetachably; lsupport-ledgasebusponduction tubes for interconnecting,

said code; pointsfzand selectedones of saidA output rcircuiiS, f andapparatus interconnected with. said output lcircuits, responsive to :theapplication ofi said;predetermi.n ed electrical condition( to saidcodelpoints through said gaseous conducingl linefconnected tofsaidswitching-center, afplu-r.

rality ofl output circuits tdwhich acall maybe.;

directed interconnected with said switching center, a translating devicecomprising in combination a plurality of gaseous conduction tubes, ap-

paratus interconnected with said tubes and controlled by signalsrepresenting two digits of a directory number for selectively initiatinga discharge through one of said tubes of said plurality of tubes,apparatus interconnected with said tubes and controlled jointly bysignals representing another digit of said directory number and theinitiation of said discharge through said selected one of said tubes forinitiating a search for an idle one of a group of said output circuits,and apparatus interconnected with said tubes for translating saidsignals representing said directory number into designations of thelocation of an idle output circuit in said switching oflice. "l

5; An interconnecting arrangement comprising in combination a rst groupof conductors arranged in accordance with one coordinate of an array, asecond group of conductors arranged in accordance with anothercoordinate of said array, a plurality of two-element gas dischargetubes, means for detachably supporting one of said tubes at each of theinterconnections of said coordinates with one of said elementselectrically connected to one of said conductors and the other of saidelements electrically connected to the other of said conductors at saidintersections, means for applying a predetermined electrical conditionto a conductor of said first group of conductors, and apparatusinterconnected with each of said conductors of said second groupresponsive to the potential condition applied to said first conductorwhen said conductors are interconnected through said gaseous conductiontubes.

6. In combination in a telephone switching system, a central switchingstation, a plurality of telephone lines extending to said switchingstation, a plurality of code points, translating apparatus fortranslating signals representing numbers dialed over said lines, aplurality of conductors connected to said code points and arranged inaccordance with one coordinate of an array, a second plurality ofconductors arranged in accordance with another coordinate of said arrayand insulated from said rst plurality of conductors, a plurality ofnon-linear circuit elements, means for detachably supporting each ofsaid non-linear circuit elements at intersections of said conductors andin electrical contact with the conductors which intersect at therespective intersections, a first plurality of gaseous conduction tubes,means interconnected with said tubes and said switching centerresponsive to signals representing two dialed digits for selectivelyinitiating a discharge through one of said plurality of tubes, a secondplurality of gaseous conduction tubes, means interconnected with said ofsaid code points in response to a discharge 1,0`

through one of saidtubes'of said second pluralityY of tubes, apparatusconnected to each of saidfconductors of said second lpluralityoi'conduct-,ors4V responsive 'to lsaid predetermined voltage: conditionapplied to saidVv code point andtransmitted through said non-linearcircuit ele-- ments. Y t

FRANKKLQW. REFERENCES CITEDl The following'references are of record finthe' file of this patent:

UNITED kSTATES PATENTS Number Name n Date 2,023,589 Hersey 'Y Dec.y 10,1935 2,291,752 VParker ..-s' Aug. 4,- 1,9 42

